The length of a slice can, unlike an array change during execution. Its much like an array, but adds some more options.
At first we initialize a slice with make:
manyKnifes := make([]string, 3,5)
Where the first parameter “3” is the length of the slice and “5” is the capacity.
So
fmt.Println("How many:", len(manyKnifes))
will give you “How many: 3”.
You may append to an existing slice:
manyKnifes = append(manyKnifes, "katana", "bowie")
Slices are backed by an underlying array, which has the capacity 5 in this example. If with the append this capacity is too small, a bigger array will be allocated. So it is efficient to make the slice big enough. But with append you can grow…
See the full source on github.